This is a reland of 5ce68669

TBR=ishell@chromium.org

Original change's description:
> Enable alignment checks when reading object fields
>
> Drive-by: Fix alignment bugs caused by DCHECKS.
>
> Bug: v8:9264
>
> Change-Id: I0836b1d08fea2ce11d8f7929e12f303b6ae06efe
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1617676
> Commit-Queue: Sigurd Schneider <sigurds@chromium.org>
> Reviewed-by: Igor Sheludko <ishell@chromium.org>
> Reviewed-by: Jakob Kummerow <jkummerow@chromium.org>
> Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#61643}

Bug: v8:9264
Change-Id: Ice9b819cc29eec0c341f16ef35fad4867f5df85b
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1619754Reviewed-by: Sigurd Schneider <sigurds@chromium.org>
Reviewed-by: Jakob Kummerow <jkummerow@chromium.org>
Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Commit-Queue: Sigurd Schneider <sigurds@chromium.org>
Cr-Commit-Position: refs/heads/master@{#61664}